The aging life of cable insulation material is primarily determined by its thermal aging life, which is determined by the rate of chemical reactions such as thermal oxidation, thermal cracking, thermal oxidative cracking, and polycondensation occurring within the insulation material under thermal stress. Therefore, the thermal aging life of the insulation material directly affects the service life of the cable. Based on chemical reaction kinetics and accelerated thermal aging tests, the long-term allowable operating temperature for irradiated cross-linked cables (20-30 years) is as follows:
1. Power Cable YJV 0.6/1KV 1160°C
Based on a rated operating temperature of 1050°C, its thermal aging life exceeds 60 years.
Based on a rated operating temperature of 900°C, its thermal aging life exceeds 100 years.
2. Overhead Insulated Cable JKLYJ 10KV 1220°C
Overhead insulated cables are laid outdoors, making the insulation material's environmental and radiation resistance even more critical. Irradiation-crosslinked insulation materials undergo irradiation processing, which inherently provides excellent radiation resistance. The radiation dose applied during the crosslinking process leaves a significant safety margin from the destructive dose. The destructive dose for polyethylene is 1000 kGY, while the processing dose is approximately 200 kGY. Furthermore, due to special formulation improvements, the material remains crosslinked over a wide range. Therefore, its performance improves during the extended initial use period.
